I'm pretty sure they are still made East Anglia somewhere (broads version now though) I owned one (Marae) in Chichester harbour for about four years - loved every minute of her - they are comfortable and they sail well - Good luck
I have a Pegasus yard no 72, a fine boat, I also have the details of the yard and the name of the builder. Last year I was able to buy spare for the boat and get full details of rig set up. I do not have any of this in my office, but if you would like to e.mail me arg@sunbeam.ie I would be pleased to let you have these details
I don't think there is an owners assoc. but I would be happy to share experiences with you. I have owned my 800 for three years now and think they are great boats.